shortwave radio and amateur radio enthusiasts sharing shortwave radio reviews, news, broadcasting, pirate radio, numbers stations, interviews, and much more

Tag Archives: NIST

If you haven’t already guessed it: yes, the mystery broadcast site I posted on Thursday was WWV/WWVB in Fort Collins, Colorado. Well done, responders! Specifically, the photo shows the southern antennas of WWVB as I departed the site on Thursday, August 28, 2014; for those of you who got that detail, extra credit–!

I’d like to thank the staff at WWV/WWVB for allowing me to visit the site for the better part of the day. WWV is not officially open to tours, so this was a particular honor for me. And this was an especially fun pilgrimage, as WWV was most likely the first shortwave broadcast I ever heard: as I’ve previously noted, when I was a kid my father used to set his watch to WWV every Sunday morning. Now I’ve seen firsthand where that famous tock, tock (and accompanying characteristic tones) originate.

When I return home from my extended travels, I’ll sort through the photos I took at WWV and WWVB, and post them here on the SWLing Post.

Recording WWV

In the meantime, I have a few recordings to share with those who are interested in this mecca of chronology. Before leaving WWV, I pulled out my Tecsun PL-380 and my Zoom H2N digital recorder, and recorded all the WWV broadcast frequencies. I captured their 2.5, 5, 10, 15, 20 and even their recently reactivated 25 MHz signals.

I made these recordings in the conference room at WWVB broadcast house. As you can imagine, it was simply not at all necessary to extend the telescopic antenna. In fact, the signal was so strong, you’ll hear a slight amount of distortion in the voice audio.

Below, you can listen to the recordings of each frequency via the embedded player (click on the title to download the audio). Enjoy!

Up to this point, I used the Tecsun PL-380, but quickly realized that the ‘380 wouldn’t tune to 25 MHz. A quick look at the back of the radio revealed that the ‘380 only tunes up to 21.950 MHz (!). Believe it or not, I’d never noticed this limitation of the PL-380, likely since I rarely tune above 21 MHz for broadcast listening. Learn something new every day…But I couldn’t fail to complete my recordings.

So what did I do? I turned to Matthew Deutch, Chief Engineer at WWV and WWVB, who kindly allowed me to use their Sangean ATS-505 to make the final recording:

Want to catch WWV–the Fort Collins-based time station–on a frequency they haven’t used since 1977?

The National Institute for Standards and Technology (NIST) has sent out a press release stating that, as of April 4, 2014, WWV will resume broadcasting on 25 Mhz for a limited time.

Full details follow in their press release:

NOTICE: Experimental 25 MHz WWV Broadcast

As of Friday, April 4, 2014 WWV has resumed broadcasting on 25 MHz on a limited, experimental basis. The broadcast consists of the normal WWV signal heard on all other WWV frequencies, at the same level of accuracy.

Current 25 MHz Broadcast Specifications (subject to change):
Schedule: variable; as an experimental broadcast, the 25 MHz signal is not continuous. It will typically be on the air from approximately 1500 – 2100 UTC Mondays through Fridays, but may operate outside these hours as well. The broadcast may be interrupted or suspended without notice.

Every night, while millions of Americans are fast asleep, clocks and wristwatches across the country wake up and lock on to a radio signal beamed from the base of the Rocky Mountains. The signal contains a message that keeps the devices on time, helping to make sure their owners keep to their schedules and aren’t late for work the next day.

The broadcast comes from WWVB, a station run by the National Institute for Standards and Technology. WWVB marks half a century as the nation’s official time broadcaster on July 5. Together with its sister station, WWV, which is about to hit 90 years in service, NIST radio has been an invisible piece of American infrastructure that has advanced industries from entertainment to telecommunications. (WWV’s broadcast includes a wider range of information, including maritime weather warnings and solar storm alerts).

Most people aren’t even aware that these stations exist, but they have a rich and fascinating history. Their future is uncertain, however, as newer technologies threaten to make them obsolete.

[…]WWV began broadcasting reference frequencies for signal calibration using equipment not that different from the chunk of quartz in a modern wristwatch. These days, though, a bit of quantum physics keeps the nation’s signals in sync. Cesium-133 atoms within the NIST-F1 atomic clock oscillate a frantic 9,192,631,770 times per second, acting like the pendulum of a grandfather clock. By tuning into that oscillation, NIST defines the basic unit of time, and by extension, frequency. Over the years, the reference frequencies have been so finely calibrated that they are accurate to beyond a single cycle in a trillion.

[…]WWVB’s value might have a lot to do with the type of signal it broadcasts and its location. While most commercial radio waves measure only a few meters between peaks, WWVB’s low frequency signal results in a whopping five kilometer wavelength. These long-wavelength signals can reach around the curvature of the planet by clinging to the semi-conductive surface of the Earth. On a clear night, a radio-controlled watch can pick up WWVB’s 60 kHz signal as far away as Patagonia or New Zealand.[…]

Many readers know that I’m a bit of a WWV geek, so you can imagine how happy I was when my buddy, Mike, and the Southgate ARC made me aware of this 152 page history of the NIST time station family. At first glance, this looks to be an authoritative and thorough history indeed.

IMPORTANT NOTICE FOR WWVB RADIO STATION USERS Radio Station WWVB will be conducting a test of a new broadcast formatfrom Monday, March 5th, 2012 at 5 p.m. MST through Saturday, March 10th at noon MST.

During the test, Station WWVB will be broadcasting amplitude modulation and phase modulation simultaneously.

This test may affect WWVB timing equipment, but consumer radio-controlled clocks should work fine during this test.

You are encouraged to direct your questions to the Broadcast Manager John Lowe: 303-497-5453 or lowe@nist.gov

NIST radio station, WWVB, is located on the same site as WWV near Fort Collins, Colorado. WWVB broadcasts are used by consumer electronic products like wall clocks, clock radios, and wristwatches which sync to its unique time code broadcast stream. WWVB is also used for high level applications such as network time synchronization and frequency calibrations.

Though the tests are being conducted over 5 days, timing may be less than desirable considering the pending solar flare.